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<FONT color="green">001</FONT>    /*<a name="line.1"></a>
<FONT color="green">002</FONT>     * Licensed to the Apache Software Foundation (ASF) under one or more<a name="line.2"></a>
<FONT color="green">003</FONT>     * contributor license agreements.  See the NOTICE file distributed with<a name="line.3"></a>
<FONT color="green">004</FONT>     * this work for additional information regarding copyright ownership.<a name="line.4"></a>
<FONT color="green">005</FONT>     * The ASF licenses this file to You under the Apache License, Version 2.0<a name="line.5"></a>
<FONT color="green">006</FONT>     * (the "License"); you may not use this file except in compliance with<a name="line.6"></a>
<FONT color="green">007</FONT>     * the License.  You may obtain a copy of the License at<a name="line.7"></a>
<FONT color="green">008</FONT>     *<a name="line.8"></a>
<FONT color="green">009</FONT>     *      http://www.apache.org/licenses/LICENSE-2.0<a name="line.9"></a>
<FONT color="green">010</FONT>     *<a name="line.10"></a>
<FONT color="green">011</FONT>     * Unless required by applicable law or agreed to in writing, software<a name="line.11"></a>
<FONT color="green">012</FONT>     * distributed under the License is distributed on an "AS IS" BASIS,<a name="line.12"></a>
<FONT color="green">013</FONT>     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.<a name="line.13"></a>
<FONT color="green">014</FONT>     * See the License for the specific language governing permissions and<a name="line.14"></a>
<FONT color="green">015</FONT>     * limitations under the License.<a name="line.15"></a>
<FONT color="green">016</FONT>     */<a name="line.16"></a>
<FONT color="green">017</FONT>    package org.apache.commons.lang3;<a name="line.17"></a>
<FONT color="green">018</FONT>    <a name="line.18"></a>
<FONT color="green">019</FONT>    import java.io.Serializable;<a name="line.19"></a>
<FONT color="green">020</FONT>    import java.lang.reflect.Array;<a name="line.20"></a>
<FONT color="green">021</FONT>    import java.lang.reflect.InvocationTargetException;<a name="line.21"></a>
<FONT color="green">022</FONT>    import java.lang.reflect.Method;<a name="line.22"></a>
<FONT color="green">023</FONT>    import java.util.Collections;<a name="line.23"></a>
<FONT color="green">024</FONT>    import java.util.Comparator;<a name="line.24"></a>
<FONT color="green">025</FONT>    import java.util.HashMap;<a name="line.25"></a>
<FONT color="green">026</FONT>    import java.util.Map;<a name="line.26"></a>
<FONT color="green">027</FONT>    import java.util.TreeSet;<a name="line.27"></a>
<FONT color="green">028</FONT>    <a name="line.28"></a>
<FONT color="green">029</FONT>    import org.apache.commons.lang3.exception.CloneFailedException;<a name="line.29"></a>
<FONT color="green">030</FONT>    import org.apache.commons.lang3.mutable.MutableInt;<a name="line.30"></a>
<FONT color="green">031</FONT>    <a name="line.31"></a>
<FONT color="green">032</FONT>    /**<a name="line.32"></a>
<FONT color="green">033</FONT>     * &lt;p&gt;Operations on {@code Object}.&lt;/p&gt;<a name="line.33"></a>
<FONT color="green">034</FONT>     *<a name="line.34"></a>
<FONT color="green">035</FONT>     * &lt;p&gt;This class tries to handle {@code null} input gracefully.<a name="line.35"></a>
<FONT color="green">036</FONT>     * An exception will generally not be thrown for a {@code null} input.<a name="line.36"></a>
<FONT color="green">037</FONT>     * Each method documents its behaviour in more detail.&lt;/p&gt;<a name="line.37"></a>
<FONT color="green">038</FONT>     *<a name="line.38"></a>
<FONT color="green">039</FONT>     * &lt;p&gt;#ThreadSafe#&lt;/p&gt;<a name="line.39"></a>
<FONT color="green">040</FONT>     * @since 1.0<a name="line.40"></a>
<FONT color="green">041</FONT>     * @version $Id: ObjectUtils.java 1199894 2011-11-09 17:53:59Z ggregory $<a name="line.41"></a>
<FONT color="green">042</FONT>     */<a name="line.42"></a>
<FONT color="green">043</FONT>    //@Immutable<a name="line.43"></a>
<FONT color="green">044</FONT>    public class ObjectUtils {<a name="line.44"></a>
<FONT color="green">045</FONT>    <a name="line.45"></a>
<FONT color="green">046</FONT>        /**<a name="line.46"></a>
<FONT color="green">047</FONT>         * &lt;p&gt;Singleton used as a {@code null} placeholder where<a name="line.47"></a>
<FONT color="green">048</FONT>         * {@code null} has another meaning.&lt;/p&gt;<a name="line.48"></a>
<FONT color="green">049</FONT>         *<a name="line.49"></a>
<FONT color="green">050</FONT>         * &lt;p&gt;For example, in a {@code HashMap} the<a name="line.50"></a>
<FONT color="green">051</FONT>         * {@link java.util.HashMap#get(java.lang.Object)} method returns<a name="line.51"></a>
<FONT color="green">052</FONT>         * {@code null} if the {@code Map} contains {@code null} or if there<a name="line.52"></a>
<FONT color="green">053</FONT>         * is no matching key. The {@code Null} placeholder can be used to<a name="line.53"></a>
<FONT color="green">054</FONT>         * distinguish between these two cases.&lt;/p&gt;<a name="line.54"></a>
<FONT color="green">055</FONT>         *<a name="line.55"></a>
<FONT color="green">056</FONT>         * &lt;p&gt;Another example is {@code Hashtable}, where {@code null}<a name="line.56"></a>
<FONT color="green">057</FONT>         * cannot be stored.&lt;/p&gt;<a name="line.57"></a>
<FONT color="green">058</FONT>         *<a name="line.58"></a>
<FONT color="green">059</FONT>         * &lt;p&gt;This instance is Serializable.&lt;/p&gt;<a name="line.59"></a>
<FONT color="green">060</FONT>         */<a name="line.60"></a>
<FONT color="green">061</FONT>        public static final Null NULL = new Null();<a name="line.61"></a>
<FONT color="green">062</FONT>    <a name="line.62"></a>
<FONT color="green">063</FONT>        /**<a name="line.63"></a>
<FONT color="green">064</FONT>         * &lt;p&gt;{@code ObjectUtils} instances should NOT be constructed in<a name="line.64"></a>
<FONT color="green">065</FONT>         * standard programming. Instead, the static methods on the class should<a name="line.65"></a>
<FONT color="green">066</FONT>         * be used, such as {@code ObjectUtils.defaultIfNull("a","b");}.&lt;/p&gt;<a name="line.66"></a>
<FONT color="green">067</FONT>         *<a name="line.67"></a>
<FONT color="green">068</FONT>         * &lt;p&gt;This constructor is public to permit tools that require a JavaBean<a name="line.68"></a>
<FONT color="green">069</FONT>         * instance to operate.&lt;/p&gt;<a name="line.69"></a>
<FONT color="green">070</FONT>         */<a name="line.70"></a>
<FONT color="green">071</FONT>        public ObjectUtils() {<a name="line.71"></a>
<FONT color="green">072</FONT>            super();<a name="line.72"></a>
<FONT color="green">073</FONT>        }<a name="line.73"></a>
<FONT color="green">074</FONT>    <a name="line.74"></a>
<FONT color="green">075</FONT>        // Defaulting<a name="line.75"></a>
<FONT color="green">076</FONT>        //-----------------------------------------------------------------------<a name="line.76"></a>
<FONT color="green">077</FONT>        /**<a name="line.77"></a>
<FONT color="green">078</FONT>         * &lt;p&gt;Returns a default value if the object passed is {@code null}.&lt;/p&gt;<a name="line.78"></a>
<FONT color="green">079</FONT>         *<a name="line.79"></a>
<FONT color="green">080</FONT>         * &lt;pre&gt;<a name="line.80"></a>
<FONT color="green">081</FONT>         * ObjectUtils.defaultIfNull(null, null)      = null<a name="line.81"></a>
<FONT color="green">082</FONT>         * ObjectUtils.defaultIfNull(null, "")        = ""<a name="line.82"></a>
<FONT color="green">083</FONT>         * ObjectUtils.defaultIfNull(null, "zz")      = "zz"<a name="line.83"></a>
<FONT color="green">084</FONT>         * ObjectUtils.defaultIfNull("abc", *)        = "abc"<a name="line.84"></a>
<FONT color="green">085</FONT>         * ObjectUtils.defaultIfNull(Boolean.TRUE, *) = Boolean.TRUE<a name="line.85"></a>
<FONT color="green">086</FONT>         * &lt;/pre&gt;<a name="line.86"></a>
<FONT color="green">087</FONT>         *<a name="line.87"></a>
<FONT color="green">088</FONT>         * @param &lt;T&gt; the type of the object<a name="line.88"></a>
<FONT color="green">089</FONT>         * @param object  the {@code Object} to test, may be {@code null}<a name="line.89"></a>
<FONT color="green">090</FONT>         * @param defaultValue  the default value to return, may be {@code null}<a name="line.90"></a>
<FONT color="green">091</FONT>         * @return {@code object} if it is not {@code null}, defaultValue otherwise<a name="line.91"></a>
<FONT color="green">092</FONT>         */<a name="line.92"></a>
<FONT color="green">093</FONT>        public static &lt;T&gt; T defaultIfNull(T object, T defaultValue) {<a name="line.93"></a>
<FONT color="green">094</FONT>            return object != null ? object : defaultValue;<a name="line.94"></a>
<FONT color="green">095</FONT>        }<a name="line.95"></a>
<FONT color="green">096</FONT>    <a name="line.96"></a>
<FONT color="green">097</FONT>        /**<a name="line.97"></a>
<FONT color="green">098</FONT>         * &lt;p&gt;Returns the first value in the array which is not {@code null}.<a name="line.98"></a>
<FONT color="green">099</FONT>         * If all the values are {@code null} or the array is {@code null}<a name="line.99"></a>
<FONT color="green">100</FONT>         * or empty then {@code null} is returned.&lt;/p&gt;<a name="line.100"></a>
<FONT color="green">101</FONT>         *<a name="line.101"></a>
<FONT color="green">102</FONT>         * &lt;pre&gt;<a name="line.102"></a>
<FONT color="green">103</FONT>         * ObjectUtils.firstNonNull(null, null)      = null<a name="line.103"></a>
<FONT color="green">104</FONT>         * ObjectUtils.firstNonNull(null, "")        = ""<a name="line.104"></a>
<FONT color="green">105</FONT>         * ObjectUtils.firstNonNull(null, null, "")  = ""<a name="line.105"></a>
<FONT color="green">106</FONT>         * ObjectUtils.firstNonNull(null, "zz")      = "zz"<a name="line.106"></a>
<FONT color="green">107</FONT>         * ObjectUtils.firstNonNull("abc", *)        = "abc"<a name="line.107"></a>
<FONT color="green">108</FONT>         * ObjectUtils.firstNonNull(null, "xyz", *)  = "xyz"<a name="line.108"></a>
<FONT color="green">109</FONT>         * ObjectUtils.firstNonNull(Boolean.TRUE, *) = Boolean.TRUE<a name="line.109"></a>
<FONT color="green">110</FONT>         * ObjectUtils.firstNonNull()                = null<a name="line.110"></a>
<FONT color="green">111</FONT>         * &lt;/pre&gt;<a name="line.111"></a>
<FONT color="green">112</FONT>         *<a name="line.112"></a>
<FONT color="green">113</FONT>         * @param &lt;T&gt; the component type of the array<a name="line.113"></a>
<FONT color="green">114</FONT>         * @param values  the values to test, may be {@code null} or empty<a name="line.114"></a>
<FONT color="green">115</FONT>         * @return the first value from {@code values} which is not {@code null},<a name="line.115"></a>
<FONT color="green">116</FONT>         *  or {@code null} if there are no non-null values<a name="line.116"></a>
<FONT color="green">117</FONT>         * @since 3.0<a name="line.117"></a>
<FONT color="green">118</FONT>         */<a name="line.118"></a>
<FONT color="green">119</FONT>        public static &lt;T&gt; T firstNonNull(T... values) {<a name="line.119"></a>
<FONT color="green">120</FONT>            if (values != null) {<a name="line.120"></a>
<FONT color="green">121</FONT>                for (T val : values) {<a name="line.121"></a>
<FONT color="green">122</FONT>                    if (val != null) {<a name="line.122"></a>
<FONT color="green">123</FONT>                        return val;<a name="line.123"></a>
<FONT color="green">124</FONT>                    }<a name="line.124"></a>
<FONT color="green">125</FONT>                }<a name="line.125"></a>
<FONT color="green">126</FONT>            }<a name="line.126"></a>
<FONT color="green">127</FONT>            return null;<a name="line.127"></a>
<FONT color="green">128</FONT>        }<a name="line.128"></a>
<FONT color="green">129</FONT>    <a name="line.129"></a>
<FONT color="green">130</FONT>        // Null-safe equals/hashCode<a name="line.130"></a>
<FONT color="green">131</FONT>        //-----------------------------------------------------------------------<a name="line.131"></a>
<FONT color="green">132</FONT>        /**<a name="line.132"></a>
<FONT color="green">133</FONT>         * &lt;p&gt;Compares two objects for equality, where either one or both<a name="line.133"></a>
<FONT color="green">134</FONT>         * objects may be {@code null}.&lt;/p&gt;<a name="line.134"></a>
<FONT color="green">135</FONT>         *<a name="line.135"></a>
<FONT color="green">136</FONT>         * &lt;pre&gt;<a name="line.136"></a>
<FONT color="green">137</FONT>         * ObjectUtils.equals(null, null)                  = true<a name="line.137"></a>
<FONT color="green">138</FONT>         * ObjectUtils.equals(null, "")                    = false<a name="line.138"></a>
<FONT color="green">139</FONT>         * ObjectUtils.equals("", null)                    = false<a name="line.139"></a>
<FONT color="green">140</FONT>         * ObjectUtils.equals("", "")                      = true<a name="line.140"></a>
<FONT color="green">141</FONT>         * ObjectUtils.equals(Boolean.TRUE, null)          = false<a name="line.141"></a>
<FONT color="green">142</FONT>         * ObjectUtils.equals(Boolean.TRUE, "true")        = false<a name="line.142"></a>
<FONT color="green">143</FONT>         * ObjectUtils.equals(Boolean.TRUE, Boolean.TRUE)  = true<a name="line.143"></a>
<FONT color="green">144</FONT>         * ObjectUtils.equals(Boolean.TRUE, Boolean.FALSE) = false<a name="line.144"></a>
<FONT color="green">145</FONT>         * &lt;/pre&gt;<a name="line.145"></a>
<FONT color="green">146</FONT>         *<a name="line.146"></a>
<FONT color="green">147</FONT>         * @param object1  the first object, may be {@code null}<a name="line.147"></a>
<FONT color="green">148</FONT>         * @param object2  the second object, may be {@code null}<a name="line.148"></a>
<FONT color="green">149</FONT>         * @return {@code true} if the values of both objects are the same<a name="line.149"></a>
<FONT color="green">150</FONT>         */<a name="line.150"></a>
<FONT color="green">151</FONT>        public static boolean equals(Object object1, Object object2) {<a name="line.151"></a>
<FONT color="green">152</FONT>            if (object1 == object2) {<a name="line.152"></a>
<FONT color="green">153</FONT>                return true;<a name="line.153"></a>
<FONT color="green">154</FONT>            }<a name="line.154"></a>
<FONT color="green">155</FONT>            if (object1 == null || object2 == null) {<a name="line.155"></a>
<FONT color="green">156</FONT>                return false;<a name="line.156"></a>
<FONT color="green">157</FONT>            }<a name="line.157"></a>
<FONT color="green">158</FONT>            return object1.equals(object2);<a name="line.158"></a>
<FONT color="green">159</FONT>        }<a name="line.159"></a>
<FONT color="green">160</FONT>    <a name="line.160"></a>
<FONT color="green">161</FONT>        /**<a name="line.161"></a>
<FONT color="green">162</FONT>         * &lt;p&gt;Compares two objects for inequality, where either one or both<a name="line.162"></a>
<FONT color="green">163</FONT>         * objects may be {@code null}.&lt;/p&gt;<a name="line.163"></a>
<FONT color="green">164</FONT>         *<a name="line.164"></a>
<FONT color="green">165</FONT>         * &lt;pre&gt;<a name="line.165"></a>
<FONT color="green">166</FONT>         * ObjectUtils.notEqual(null, null)                  = false<a name="line.166"></a>
<FONT color="green">167</FONT>         * ObjectUtils.notEqual(null, "")                    = true<a name="line.167"></a>
<FONT color="green">168</FONT>         * ObjectUtils.notEqual("", null)                    = true<a name="line.168"></a>
<FONT color="green">169</FONT>         * ObjectUtils.notEqual("", "")                      = false<a name="line.169"></a>
<FONT color="green">170</FONT>         * ObjectUtils.notEqual(Boolean.TRUE, null)          = true<a name="line.170"></a>
<FONT color="green">171</FONT>         * ObjectUtils.notEqual(Boolean.TRUE, "true")        = true<a name="line.171"></a>
<FONT color="green">172</FONT>         * ObjectUtils.notEqual(Boolean.TRUE, Boolean.TRUE)  = false<a name="line.172"></a>
<FONT color="green">173</FONT>         * ObjectUtils.notEqual(Boolean.TRUE, Boolean.FALSE) = true<a name="line.173"></a>
<FONT color="green">174</FONT>         * &lt;/pre&gt;<a name="line.174"></a>
<FONT color="green">175</FONT>         *<a name="line.175"></a>
<FONT color="green">176</FONT>         * @param object1  the first object, may be {@code null}<a name="line.176"></a>
<FONT color="green">177</FONT>         * @param object2  the second object, may be {@code null}<a name="line.177"></a>
<FONT color="green">178</FONT>         * @return {@code false} if the values of both objects are the same<a name="line.178"></a>
<FONT color="green">179</FONT>         */<a name="line.179"></a>
<FONT color="green">180</FONT>        public static boolean notEqual(Object object1, Object object2) {<a name="line.180"></a>
<FONT color="green">181</FONT>            return ObjectUtils.equals(object1, object2) == false;<a name="line.181"></a>
<FONT color="green">182</FONT>        }<a name="line.182"></a>
<FONT color="green">183</FONT>    <a name="line.183"></a>
<FONT color="green">184</FONT>        /**<a name="line.184"></a>
<FONT color="green">185</FONT>         * &lt;p&gt;Gets the hash code of an object returning zero when the<a name="line.185"></a>
<FONT color="green">186</FONT>         * object is {@code null}.&lt;/p&gt;<a name="line.186"></a>
<FONT color="green">187</FONT>         *<a name="line.187"></a>
<FONT color="green">188</FONT>         * &lt;pre&gt;<a name="line.188"></a>
<FONT color="green">189</FONT>         * ObjectUtils.hashCode(null)   = 0<a name="line.189"></a>
<FONT color="green">190</FONT>         * ObjectUtils.hashCode(obj)    = obj.hashCode()<a name="line.190"></a>
<FONT color="green">191</FONT>         * &lt;/pre&gt;<a name="line.191"></a>
<FONT color="green">192</FONT>         *<a name="line.192"></a>
<FONT color="green">193</FONT>         * @param obj  the object to obtain the hash code of, may be {@code null}<a name="line.193"></a>
<FONT color="green">194</FONT>         * @return the hash code of the object, or zero if null<a name="line.194"></a>
<FONT color="green">195</FONT>         * @since 2.1<a name="line.195"></a>
<FONT color="green">196</FONT>         */<a name="line.196"></a>
<FONT color="green">197</FONT>        public static int hashCode(Object obj) {<a name="line.197"></a>
<FONT color="green">198</FONT>            // hashCode(Object) retained for performance, as hash code is often critical<a name="line.198"></a>
<FONT color="green">199</FONT>            return obj == null ? 0 : obj.hashCode();<a name="line.199"></a>
<FONT color="green">200</FONT>        }<a name="line.200"></a>
<FONT color="green">201</FONT>    <a name="line.201"></a>
<FONT color="green">202</FONT>        /**<a name="line.202"></a>
<FONT color="green">203</FONT>         * &lt;p&gt;Gets the hash code for multiple objects.&lt;/p&gt;<a name="line.203"></a>
<FONT color="green">204</FONT>         * <a name="line.204"></a>
<FONT color="green">205</FONT>         * &lt;p&gt;This allows a hash code to be rapidly calculated for a number of objects.<a name="line.205"></a>
<FONT color="green">206</FONT>         * The hash code for a single object is the &lt;em&gt;not&lt;/em&gt; same as {@link #hashCode(Object)}.<a name="line.206"></a>
<FONT color="green">207</FONT>         * The hash code for multiple objects is the same as that calculated by an<a name="line.207"></a>
<FONT color="green">208</FONT>         * {@code ArrayList} containing the specified objects.&lt;/p&gt;<a name="line.208"></a>
<FONT color="green">209</FONT>         *<a name="line.209"></a>
<FONT color="green">210</FONT>         * &lt;pre&gt;<a name="line.210"></a>
<FONT color="green">211</FONT>         * ObjectUtils.hashCodeMulti()                 = 1<a name="line.211"></a>
<FONT color="green">212</FONT>         * ObjectUtils.hashCodeMulti((Object[]) null)  = 1<a name="line.212"></a>
<FONT color="green">213</FONT>         * ObjectUtils.hashCodeMulti(a)                = 31 + a.hashCode()<a name="line.213"></a>
<FONT color="green">214</FONT>         * ObjectUtils.hashCodeMulti(a,b)              = (31 + a.hashCode()) * 31 + b.hashCode()<a name="line.214"></a>
<FONT color="green">215</FONT>         * ObjectUtils.hashCodeMulti(a,b,c)            = ((31 + a.hashCode()) * 31 + b.hashCode()) * 31 + c.hashCode()<a name="line.215"></a>
<FONT color="green">216</FONT>         * &lt;/pre&gt;<a name="line.216"></a>
<FONT color="green">217</FONT>         *<a name="line.217"></a>
<FONT color="green">218</FONT>         * @param objects  the objects to obtain the hash code of, may be {@code null}<a name="line.218"></a>
<FONT color="green">219</FONT>         * @return the hash code of the objects, or zero if null<a name="line.219"></a>
<FONT color="green">220</FONT>         * @since 3.0<a name="line.220"></a>
<FONT color="green">221</FONT>         */<a name="line.221"></a>
<FONT color="green">222</FONT>        public static int hashCodeMulti(Object... objects) {<a name="line.222"></a>
<FONT color="green">223</FONT>            int hash = 1;<a name="line.223"></a>
<FONT color="green">224</FONT>            if (objects != null) {<a name="line.224"></a>
<FONT color="green">225</FONT>                for (Object object : objects) {<a name="line.225"></a>
<FONT color="green">226</FONT>                    hash = hash * 31 + ObjectUtils.hashCode(object);<a name="line.226"></a>
<FONT color="green">227</FONT>                }<a name="line.227"></a>
<FONT color="green">228</FONT>            }<a name="line.228"></a>
<FONT color="green">229</FONT>            return hash;<a name="line.229"></a>
<FONT color="green">230</FONT>        }<a name="line.230"></a>
<FONT color="green">231</FONT>    <a name="line.231"></a>
<FONT color="green">232</FONT>        // Identity ToString<a name="line.232"></a>
<FONT color="green">233</FONT>        //-----------------------------------------------------------------------<a name="line.233"></a>
<FONT color="green">234</FONT>        /**<a name="line.234"></a>
<FONT color="green">235</FONT>         * &lt;p&gt;Gets the toString that would be produced by {@code Object}<a name="line.235"></a>
<FONT color="green">236</FONT>         * if a class did not override toString itself. {@code null}<a name="line.236"></a>
<FONT color="green">237</FONT>         * will return {@code null}.&lt;/p&gt;<a name="line.237"></a>
<FONT color="green">238</FONT>         *<a name="line.238"></a>
<FONT color="green">239</FONT>         * &lt;pre&gt;<a name="line.239"></a>
<FONT color="green">240</FONT>         * ObjectUtils.identityToString(null)         = null<a name="line.240"></a>
<FONT color="green">241</FONT>         * ObjectUtils.identityToString("")           = "java.lang.String@1e23"<a name="line.241"></a>
<FONT color="green">242</FONT>         * ObjectUtils.identityToString(Boolean.TRUE) = "java.lang.Boolean@7fa"<a name="line.242"></a>
<FONT color="green">243</FONT>         * &lt;/pre&gt;<a name="line.243"></a>
<FONT color="green">244</FONT>         *<a name="line.244"></a>
<FONT color="green">245</FONT>         * @param object  the object to create a toString for, may be<a name="line.245"></a>
<FONT color="green">246</FONT>         *  {@code null}<a name="line.246"></a>
<FONT color="green">247</FONT>         * @return the default toString text, or {@code null} if<a name="line.247"></a>
<FONT color="green">248</FONT>         *  {@code null} passed in<a name="line.248"></a>
<FONT color="green">249</FONT>         */<a name="line.249"></a>
<FONT color="green">250</FONT>        public static String identityToString(Object object) {<a name="line.250"></a>
<FONT color="green">251</FONT>            if (object == null) {<a name="line.251"></a>
<FONT color="green">252</FONT>                return null;<a name="line.252"></a>
<FONT color="green">253</FONT>            }<a name="line.253"></a>
<FONT color="green">254</FONT>            StringBuffer buffer = new StringBuffer();<a name="line.254"></a>
<FONT color="green">255</FONT>            identityToString(buffer, object);<a name="line.255"></a>
<FONT color="green">256</FONT>            return buffer.toString();<a name="line.256"></a>
<FONT color="green">257</FONT>        }<a name="line.257"></a>
<FONT color="green">258</FONT>    <a name="line.258"></a>
<FONT color="green">259</FONT>        /**<a name="line.259"></a>
<FONT color="green">260</FONT>         * &lt;p&gt;Appends the toString that would be produced by {@code Object}<a name="line.260"></a>
<FONT color="green">261</FONT>         * if a class did not override toString itself. {@code null}<a name="line.261"></a>
<FONT color="green">262</FONT>         * will throw a NullPointerException for either of the two parameters. &lt;/p&gt;<a name="line.262"></a>
<FONT color="green">263</FONT>         *<a name="line.263"></a>
<FONT color="green">264</FONT>         * &lt;pre&gt;<a name="line.264"></a>
<FONT color="green">265</FONT>         * ObjectUtils.identityToString(buf, "")            = buf.append("java.lang.String@1e23"<a name="line.265"></a>
<FONT color="green">266</FONT>         * ObjectUtils.identityToString(buf, Boolean.TRUE)  = buf.append("java.lang.Boolean@7fa"<a name="line.266"></a>
<FONT color="green">267</FONT>         * ObjectUtils.identityToString(buf, Boolean.TRUE)  = buf.append("java.lang.Boolean@7fa")<a name="line.267"></a>
<FONT color="green">268</FONT>         * &lt;/pre&gt;<a name="line.268"></a>
<FONT color="green">269</FONT>         *<a name="line.269"></a>
<FONT color="green">270</FONT>         * @param buffer  the buffer to append to<a name="line.270"></a>
<FONT color="green">271</FONT>         * @param object  the object to create a toString for<a name="line.271"></a>
<FONT color="green">272</FONT>         * @since 2.4<a name="line.272"></a>
<FONT color="green">273</FONT>         */<a name="line.273"></a>
<FONT color="green">274</FONT>        public static void identityToString(StringBuffer buffer, Object object) {<a name="line.274"></a>
<FONT color="green">275</FONT>            if (object == null) {<a name="line.275"></a>
<FONT color="green">276</FONT>                throw new NullPointerException("Cannot get the toString of a null identity");<a name="line.276"></a>
<FONT color="green">277</FONT>            }<a name="line.277"></a>
<FONT color="green">278</FONT>            buffer.append(object.getClass().getName())<a name="line.278"></a>
<FONT color="green">279</FONT>                  .append('@')<a name="line.279"></a>
<FONT color="green">280</FONT>                  .append(Integer.toHexString(System.identityHashCode(object)));<a name="line.280"></a>
<FONT color="green">281</FONT>        }<a name="line.281"></a>
<FONT color="green">282</FONT>    <a name="line.282"></a>
<FONT color="green">283</FONT>        // ToString<a name="line.283"></a>
<FONT color="green">284</FONT>        //-----------------------------------------------------------------------<a name="line.284"></a>
<FONT color="green">285</FONT>        /**<a name="line.285"></a>
<FONT color="green">286</FONT>         * &lt;p&gt;Gets the {@code toString} of an {@code Object} returning<a name="line.286"></a>
<FONT color="green">287</FONT>         * an empty string ("") if {@code null} input.&lt;/p&gt;<a name="line.287"></a>
<FONT color="green">288</FONT>         *<a name="line.288"></a>
<FONT color="green">289</FONT>         * &lt;pre&gt;<a name="line.289"></a>
<FONT color="green">290</FONT>         * ObjectUtils.toString(null)         = ""<a name="line.290"></a>
<FONT color="green">291</FONT>         * ObjectUtils.toString("")           = ""<a name="line.291"></a>
<FONT color="green">292</FONT>         * ObjectUtils.toString("bat")        = "bat"<a name="line.292"></a>
<FONT color="green">293</FONT>         * ObjectUtils.toString(Boolean.TRUE) = "true"<a name="line.293"></a>
<FONT color="green">294</FONT>         * &lt;/pre&gt;<a name="line.294"></a>
<FONT color="green">295</FONT>         *<a name="line.295"></a>
<FONT color="green">296</FONT>         * @see StringUtils#defaultString(String)<a name="line.296"></a>
<FONT color="green">297</FONT>         * @see String#valueOf(Object)<a name="line.297"></a>
<FONT color="green">298</FONT>         * @param obj  the Object to {@code toString}, may be null<a name="line.298"></a>
<FONT color="green">299</FONT>         * @return the passed in Object's toString, or nullStr if {@code null} input<a name="line.299"></a>
<FONT color="green">300</FONT>         * @since 2.0<a name="line.300"></a>
<FONT color="green">301</FONT>         */<a name="line.301"></a>
<FONT color="green">302</FONT>        public static String toString(Object obj) {<a name="line.302"></a>
<FONT color="green">303</FONT>            return obj == null ? "" : obj.toString();<a name="line.303"></a>
<FONT color="green">304</FONT>        }<a name="line.304"></a>
<FONT color="green">305</FONT>    <a name="line.305"></a>
<FONT color="green">306</FONT>        /**<a name="line.306"></a>
<FONT color="green">307</FONT>         * &lt;p&gt;Gets the {@code toString} of an {@code Object} returning<a name="line.307"></a>
<FONT color="green">308</FONT>         * a specified text if {@code null} input.&lt;/p&gt;<a name="line.308"></a>
<FONT color="green">309</FONT>         *<a name="line.309"></a>
<FONT color="green">310</FONT>         * &lt;pre&gt;<a name="line.310"></a>
<FONT color="green">311</FONT>         * ObjectUtils.toString(null, null)           = null<a name="line.311"></a>
<FONT color="green">312</FONT>         * ObjectUtils.toString(null, "null")         = "null"<a name="line.312"></a>
<FONT color="green">313</FONT>         * ObjectUtils.toString("", "null")           = ""<a name="line.313"></a>
<FONT color="green">314</FONT>         * ObjectUtils.toString("bat", "null")        = "bat"<a name="line.314"></a>
<FONT color="green">315</FONT>         * ObjectUtils.toString(Boolean.TRUE, "null") = "true"<a name="line.315"></a>
<FONT color="green">316</FONT>         * &lt;/pre&gt;<a name="line.316"></a>
<FONT color="green">317</FONT>         *<a name="line.317"></a>
<FONT color="green">318</FONT>         * @see StringUtils#defaultString(String,String)<a name="line.318"></a>
<FONT color="green">319</FONT>         * @see String#valueOf(Object)<a name="line.319"></a>
<FONT color="green">320</FONT>         * @param obj  the Object to {@code toString}, may be null<a name="line.320"></a>
<FONT color="green">321</FONT>         * @param nullStr  the String to return if {@code null} input, may be null<a name="line.321"></a>
<FONT color="green">322</FONT>         * @return the passed in Object's toString, or nullStr if {@code null} input<a name="line.322"></a>
<FONT color="green">323</FONT>         * @since 2.0<a name="line.323"></a>
<FONT color="green">324</FONT>         */<a name="line.324"></a>
<FONT color="green">325</FONT>        public static String toString(Object obj, String nullStr) {<a name="line.325"></a>
<FONT color="green">326</FONT>            return obj == null ? nullStr : obj.toString();<a name="line.326"></a>
<FONT color="green">327</FONT>        }<a name="line.327"></a>
<FONT color="green">328</FONT>    <a name="line.328"></a>
<FONT color="green">329</FONT>        // Comparable<a name="line.329"></a>
<FONT color="green">330</FONT>        //-----------------------------------------------------------------------<a name="line.330"></a>
<FONT color="green">331</FONT>        /**<a name="line.331"></a>
<FONT color="green">332</FONT>         * &lt;p&gt;Null safe comparison of Comparables.&lt;/p&gt;<a name="line.332"></a>
<FONT color="green">333</FONT>         *<a name="line.333"></a>
<FONT color="green">334</FONT>         * @param &lt;T&gt; type of the values processed by this method<a name="line.334"></a>
<FONT color="green">335</FONT>         * @param values the set of comparable values, may be null<a name="line.335"></a>
<FONT color="green">336</FONT>         * @return<a name="line.336"></a>
<FONT color="green">337</FONT>         *  &lt;ul&gt;<a name="line.337"></a>
<FONT color="green">338</FONT>         *   &lt;li&gt;If any objects are non-null and unequal, the lesser object.<a name="line.338"></a>
<FONT color="green">339</FONT>         *   &lt;li&gt;If all objects are non-null and equal, the first.<a name="line.339"></a>
<FONT color="green">340</FONT>         *   &lt;li&gt;If any of the comparables are null, the lesser of the non-null objects.<a name="line.340"></a>
<FONT color="green">341</FONT>         *   &lt;li&gt;If all the comparables are null, null is returned.<a name="line.341"></a>
<FONT color="green">342</FONT>         *  &lt;/ul&gt;<a name="line.342"></a>
<FONT color="green">343</FONT>         */<a name="line.343"></a>
<FONT color="green">344</FONT>        public static &lt;T extends Comparable&lt;? super T&gt;&gt; T min(T... values) {<a name="line.344"></a>
<FONT color="green">345</FONT>            T result = null;<a name="line.345"></a>
<FONT color="green">346</FONT>            if (values != null) {<a name="line.346"></a>
<FONT color="green">347</FONT>                for (T value : values) {<a name="line.347"></a>
<FONT color="green">348</FONT>                    if (compare(value, result, true) &lt; 0) {<a name="line.348"></a>
<FONT color="green">349</FONT>                        result = value;<a name="line.349"></a>
<FONT color="green">350</FONT>                    }<a name="line.350"></a>
<FONT color="green">351</FONT>                }<a name="line.351"></a>
<FONT color="green">352</FONT>            }<a name="line.352"></a>
<FONT color="green">353</FONT>            return result;<a name="line.353"></a>
<FONT color="green">354</FONT>        }<a name="line.354"></a>
<FONT color="green">355</FONT>    <a name="line.355"></a>
<FONT color="green">356</FONT>        /**<a name="line.356"></a>
<FONT color="green">357</FONT>         * &lt;p&gt;Null safe comparison of Comparables.&lt;/p&gt;<a name="line.357"></a>
<FONT color="green">358</FONT>         *<a name="line.358"></a>
<FONT color="green">359</FONT>         * @param &lt;T&gt; type of the values processed by this method<a name="line.359"></a>
<FONT color="green">360</FONT>         * @param values the set of comparable values, may be null<a name="line.360"></a>
<FONT color="green">361</FONT>         * @return<a name="line.361"></a>
<FONT color="green">362</FONT>         *  &lt;ul&gt;<a name="line.362"></a>
<FONT color="green">363</FONT>         *   &lt;li&gt;If any objects are non-null and unequal, the greater object.<a name="line.363"></a>
<FONT color="green">364</FONT>         *   &lt;li&gt;If all objects are non-null and equal, the first.<a name="line.364"></a>
<FONT color="green">365</FONT>         *   &lt;li&gt;If any of the comparables are null, the greater of the non-null objects.<a name="line.365"></a>
<FONT color="green">366</FONT>         *   &lt;li&gt;If all the comparables are null, null is returned.<a name="line.366"></a>
<FONT color="green">367</FONT>         *  &lt;/ul&gt;<a name="line.367"></a>
<FONT color="green">368</FONT>         */<a name="line.368"></a>
<FONT color="green">369</FONT>        public static &lt;T extends Comparable&lt;? super T&gt;&gt; T max(T... values) {<a name="line.369"></a>
<FONT color="green">370</FONT>            T result = null;<a name="line.370"></a>
<FONT color="green">371</FONT>            if (values != null) {<a name="line.371"></a>
<FONT color="green">372</FONT>                for (T value : values) {<a name="line.372"></a>
<FONT color="green">373</FONT>                    if (compare(value, result, false) &gt; 0) {<a name="line.373"></a>
<FONT color="green">374</FONT>                        result = value;<a name="line.374"></a>
<FONT color="green">375</FONT>                    }<a name="line.375"></a>
<FONT color="green">376</FONT>                }<a name="line.376"></a>
<FONT color="green">377</FONT>            }<a name="line.377"></a>
<FONT color="green">378</FONT>            return result;<a name="line.378"></a>
<FONT color="green">379</FONT>        }<a name="line.379"></a>
<FONT color="green">380</FONT>    <a name="line.380"></a>
<FONT color="green">381</FONT>        /**<a name="line.381"></a>
<FONT color="green">382</FONT>         * &lt;p&gt;Null safe comparison of Comparables.<a name="line.382"></a>
<FONT color="green">383</FONT>         * {@code null} is assumed to be less than a non-{@code null} value.&lt;/p&gt;<a name="line.383"></a>
<FONT color="green">384</FONT>         *<a name="line.384"></a>
<FONT color="green">385</FONT>         * @param &lt;T&gt; type of the values processed by this method<a name="line.385"></a>
<FONT color="green">386</FONT>         * @param c1  the first comparable, may be null<a name="line.386"></a>
<FONT color="green">387</FONT>         * @param c2  the second comparable, may be null<a name="line.387"></a>
<FONT color="green">388</FONT>         * @return a negative value if c1 &lt; c2, zero if c1 = c2<a name="line.388"></a>
<FONT color="green">389</FONT>         *  and a positive value if c1 &gt; c2<a name="line.389"></a>
<FONT color="green">390</FONT>         */<a name="line.390"></a>
<FONT color="green">391</FONT>        public static &lt;T extends Comparable&lt;? super T&gt;&gt; int compare(T c1, T c2) {<a name="line.391"></a>
<FONT color="green">392</FONT>            return compare(c1, c2, false);<a name="line.392"></a>
<FONT color="green">393</FONT>        }<a name="line.393"></a>
<FONT color="green">394</FONT>    <a name="line.394"></a>
<FONT color="green">395</FONT>        /**<a name="line.395"></a>
<FONT color="green">396</FONT>         * &lt;p&gt;Null safe comparison of Comparables.&lt;/p&gt;<a name="line.396"></a>
<FONT color="green">397</FONT>         *<a name="line.397"></a>
<FONT color="green">398</FONT>         * @param &lt;T&gt; type of the values processed by this method<a name="line.398"></a>
<FONT color="green">399</FONT>         * @param c1  the first comparable, may be null<a name="line.399"></a>
<FONT color="green">400</FONT>         * @param c2  the second comparable, may be null<a name="line.400"></a>
<FONT color="green">401</FONT>         * @param nullGreater if true {@code null} is considered greater<a name="line.401"></a>
<FONT color="green">402</FONT>         *  than a non-{@code null} value or if false {@code null} is<a name="line.402"></a>
<FONT color="green">403</FONT>         *  considered less than a Non-{@code null} value<a name="line.403"></a>
<FONT color="green">404</FONT>         * @return a negative value if c1 &lt; c2, zero if c1 = c2<a name="line.404"></a>
<FONT color="green">405</FONT>         *  and a positive value if c1 &gt; c2<a name="line.405"></a>
<FONT color="green">406</FONT>         * @see java.util.Comparator#compare(Object, Object)<a name="line.406"></a>
<FONT color="green">407</FONT>         */<a name="line.407"></a>
<FONT color="green">408</FONT>        public static &lt;T extends Comparable&lt;? super T&gt;&gt; int compare(T c1, T c2, boolean nullGreater) {<a name="line.408"></a>
<FONT color="green">409</FONT>            if (c1 == c2) {<a name="line.409"></a>
<FONT color="green">410</FONT>                return 0;<a name="line.410"></a>
<FONT color="green">411</FONT>            } else if (c1 == null) {<a name="line.411"></a>
<FONT color="green">412</FONT>                return nullGreater ? 1 : -1;<a name="line.412"></a>
<FONT color="green">413</FONT>            } else if (c2 == null) {<a name="line.413"></a>
<FONT color="green">414</FONT>                return nullGreater ? -1 : 1;<a name="line.414"></a>
<FONT color="green">415</FONT>            }<a name="line.415"></a>
<FONT color="green">416</FONT>            return c1.compareTo(c2);<a name="line.416"></a>
<FONT color="green">417</FONT>        }<a name="line.417"></a>
<FONT color="green">418</FONT>    <a name="line.418"></a>
<FONT color="green">419</FONT>        /**<a name="line.419"></a>
<FONT color="green">420</FONT>         * Find the "best guess" middle value among comparables. If there is an even<a name="line.420"></a>
<FONT color="green">421</FONT>         * number of total values, the lower of the two middle values will be returned.<a name="line.421"></a>
<FONT color="green">422</FONT>         * @param &lt;T&gt; type of values processed by this method<a name="line.422"></a>
<FONT color="green">423</FONT>         * @param items to compare<a name="line.423"></a>
<FONT color="green">424</FONT>         * @return T at middle position<a name="line.424"></a>
<FONT color="green">425</FONT>         * @throws NullPointerException if items is {@code null}<a name="line.425"></a>
<FONT color="green">426</FONT>         * @throws IllegalArgumentException if items is empty or contains {@code null} values<a name="line.426"></a>
<FONT color="green">427</FONT>         * @since 3.0.1<a name="line.427"></a>
<FONT color="green">428</FONT>         */<a name="line.428"></a>
<FONT color="green">429</FONT>        public static &lt;T extends Comparable&lt;? super T&gt;&gt; T median(T... items) {<a name="line.429"></a>
<FONT color="green">430</FONT>            Validate.notEmpty(items);<a name="line.430"></a>
<FONT color="green">431</FONT>            Validate.noNullElements(items);<a name="line.431"></a>
<FONT color="green">432</FONT>            TreeSet&lt;T&gt; sort = new TreeSet&lt;T&gt;();<a name="line.432"></a>
<FONT color="green">433</FONT>            Collections.addAll(sort, items);<a name="line.433"></a>
<FONT color="green">434</FONT>            @SuppressWarnings("unchecked") //we know all items added were T instances<a name="line.434"></a>
<FONT color="green">435</FONT>            T result = (T) sort.toArray()[(sort.size() - 1) / 2];<a name="line.435"></a>
<FONT color="green">436</FONT>            return result;<a name="line.436"></a>
<FONT color="green">437</FONT>        }<a name="line.437"></a>
<FONT color="green">438</FONT>    <a name="line.438"></a>
<FONT color="green">439</FONT>        /**<a name="line.439"></a>
<FONT color="green">440</FONT>         * Find the "best guess" middle value among comparables. If there is an even<a name="line.440"></a>
<FONT color="green">441</FONT>         * number of total values, the lower of the two middle values will be returned.<a name="line.441"></a>
<FONT color="green">442</FONT>         * @param &lt;T&gt; type of values processed by this method<a name="line.442"></a>
<FONT color="green">443</FONT>         * @param comparator to use for comparisons<a name="line.443"></a>
<FONT color="green">444</FONT>         * @param items to compare<a name="line.444"></a>
<FONT color="green">445</FONT>         * @return T at middle position<a name="line.445"></a>
<FONT color="green">446</FONT>         * @throws NullPointerException if items or comparator is {@code null}<a name="line.446"></a>
<FONT color="green">447</FONT>         * @throws IllegalArgumentException if items is empty or contains {@code null} values<a name="line.447"></a>
<FONT color="green">448</FONT>         * @since 3.0.1<a name="line.448"></a>
<FONT color="green">449</FONT>         */<a name="line.449"></a>
<FONT color="green">450</FONT>        public static &lt;T&gt; T median(Comparator&lt;T&gt; comparator, T... items) {<a name="line.450"></a>
<FONT color="green">451</FONT>            Validate.notEmpty(items, "null/empty items");<a name="line.451"></a>
<FONT color="green">452</FONT>            Validate.noNullElements(items);<a name="line.452"></a>
<FONT color="green">453</FONT>            Validate.notNull(comparator, "null comparator");<a name="line.453"></a>
<FONT color="green">454</FONT>            TreeSet&lt;T&gt; sort = new TreeSet&lt;T&gt;(comparator);<a name="line.454"></a>
<FONT color="green">455</FONT>            Collections.addAll(sort, items);<a name="line.455"></a>
<FONT color="green">456</FONT>            @SuppressWarnings("unchecked") //we know all items added were T instances<a name="line.456"></a>
<FONT color="green">457</FONT>            T result = (T) sort.toArray()[(sort.size() - 1) / 2];<a name="line.457"></a>
<FONT color="green">458</FONT>            return result;<a name="line.458"></a>
<FONT color="green">459</FONT>        }<a name="line.459"></a>
<FONT color="green">460</FONT>    <a name="line.460"></a>
<FONT color="green">461</FONT>        // Mode<a name="line.461"></a>
<FONT color="green">462</FONT>        //-----------------------------------------------------------------------<a name="line.462"></a>
<FONT color="green">463</FONT>        /**<a name="line.463"></a>
<FONT color="green">464</FONT>         * Find the most frequently occurring item.<a name="line.464"></a>
<FONT color="green">465</FONT>         * <a name="line.465"></a>
<FONT color="green">466</FONT>         * @param &lt;T&gt; type of values processed by this method<a name="line.466"></a>
<FONT color="green">467</FONT>         * @param items to check<a name="line.467"></a>
<FONT color="green">468</FONT>         * @return most populous T, {@code null} if non-unique or no items supplied<a name="line.468"></a>
<FONT color="green">469</FONT>         * @since 3.0.1<a name="line.469"></a>
<FONT color="green">470</FONT>         */<a name="line.470"></a>
<FONT color="green">471</FONT>        public static &lt;T&gt; T mode(T... items) {<a name="line.471"></a>
<FONT color="green">472</FONT>            if (ArrayUtils.isNotEmpty(items)) {<a name="line.472"></a>
<FONT color="green">473</FONT>                HashMap&lt;T, MutableInt&gt; occurrences = new HashMap&lt;T, MutableInt&gt;(items.length);<a name="line.473"></a>
<FONT color="green">474</FONT>                for (T t : items) {<a name="line.474"></a>
<FONT color="green">475</FONT>                    MutableInt count = occurrences.get(t);<a name="line.475"></a>
<FONT color="green">476</FONT>                    if (count == null) {<a name="line.476"></a>
<FONT color="green">477</FONT>                        occurrences.put(t, new MutableInt(1));<a name="line.477"></a>
<FONT color="green">478</FONT>                    } else {<a name="line.478"></a>
<FONT color="green">479</FONT>                        count.increment();<a name="line.479"></a>
<FONT color="green">480</FONT>                    }<a name="line.480"></a>
<FONT color="green">481</FONT>                }<a name="line.481"></a>
<FONT color="green">482</FONT>                T result = null;<a name="line.482"></a>
<FONT color="green">483</FONT>                int max = 0;<a name="line.483"></a>
<FONT color="green">484</FONT>                for (Map.Entry&lt;T, MutableInt&gt; e : occurrences.entrySet()) {<a name="line.484"></a>
<FONT color="green">485</FONT>                    int cmp = e.getValue().intValue();<a name="line.485"></a>
<FONT color="green">486</FONT>                    if (cmp == max) {<a name="line.486"></a>
<FONT color="green">487</FONT>                        result = null;<a name="line.487"></a>
<FONT color="green">488</FONT>                    } else if (cmp &gt; max) {<a name="line.488"></a>
<FONT color="green">489</FONT>                        max = cmp;<a name="line.489"></a>
<FONT color="green">490</FONT>                        result = e.getKey();<a name="line.490"></a>
<FONT color="green">491</FONT>                    }<a name="line.491"></a>
<FONT color="green">492</FONT>                }<a name="line.492"></a>
<FONT color="green">493</FONT>                return result;<a name="line.493"></a>
<FONT color="green">494</FONT>            }<a name="line.494"></a>
<FONT color="green">495</FONT>            return null;<a name="line.495"></a>
<FONT color="green">496</FONT>        }<a name="line.496"></a>
<FONT color="green">497</FONT>    <a name="line.497"></a>
<FONT color="green">498</FONT>        // cloning<a name="line.498"></a>
<FONT color="green">499</FONT>        //-----------------------------------------------------------------------<a name="line.499"></a>
<FONT color="green">500</FONT>        /**<a name="line.500"></a>
<FONT color="green">501</FONT>         * &lt;p&gt;Clone an object.&lt;/p&gt;<a name="line.501"></a>
<FONT color="green">502</FONT>         *<a name="line.502"></a>
<FONT color="green">503</FONT>         * @param &lt;T&gt; the type of the object<a name="line.503"></a>
<FONT color="green">504</FONT>         * @param obj  the object to clone, null returns null<a name="line.504"></a>
<FONT color="green">505</FONT>         * @return the clone if the object implements {@link Cloneable} otherwise {@code null}<a name="line.505"></a>
<FONT color="green">506</FONT>         * @throws CloneFailedException if the object is cloneable and the clone operation fails<a name="line.506"></a>
<FONT color="green">507</FONT>         * @since 3.0<a name="line.507"></a>
<FONT color="green">508</FONT>         */<a name="line.508"></a>
<FONT color="green">509</FONT>        public static &lt;T&gt; T clone(final T obj) {<a name="line.509"></a>
<FONT color="green">510</FONT>            if (obj instanceof Cloneable) {<a name="line.510"></a>
<FONT color="green">511</FONT>                final Object result;<a name="line.511"></a>
<FONT color="green">512</FONT>                if (obj.getClass().isArray()) {<a name="line.512"></a>
<FONT color="green">513</FONT>                    final Class&lt;?&gt; componentType = obj.getClass().getComponentType();<a name="line.513"></a>
<FONT color="green">514</FONT>                    if (!componentType.isPrimitive()) {<a name="line.514"></a>
<FONT color="green">515</FONT>                        result = ((Object[]) obj).clone();<a name="line.515"></a>
<FONT color="green">516</FONT>                    } else {<a name="line.516"></a>
<FONT color="green">517</FONT>                        int length = Array.getLength(obj);<a name="line.517"></a>
<FONT color="green">518</FONT>                        result = Array.newInstance(componentType, length);<a name="line.518"></a>
<FONT color="green">519</FONT>                        while (length-- &gt; 0) {<a name="line.519"></a>
<FONT color="green">520</FONT>                            Array.set(result, length, Array.get(obj, length));<a name="line.520"></a>
<FONT color="green">521</FONT>                        }<a name="line.521"></a>
<FONT color="green">522</FONT>                    }<a name="line.522"></a>
<FONT color="green">523</FONT>                } else {<a name="line.523"></a>
<FONT color="green">524</FONT>                    try {<a name="line.524"></a>
<FONT color="green">525</FONT>                        final Method clone = obj.getClass().getMethod("clone");<a name="line.525"></a>
<FONT color="green">526</FONT>                        result = clone.invoke(obj);<a name="line.526"></a>
<FONT color="green">527</FONT>                    } catch (final NoSuchMethodException e) {<a name="line.527"></a>
<FONT color="green">528</FONT>                        throw new CloneFailedException("Cloneable type "<a name="line.528"></a>
<FONT color="green">529</FONT>                            + obj.getClass().getName()<a name="line.529"></a>
<FONT color="green">530</FONT>                            + " has no clone method", e);<a name="line.530"></a>
<FONT color="green">531</FONT>                    } catch (final IllegalAccessException e) {<a name="line.531"></a>
<FONT color="green">532</FONT>                        throw new CloneFailedException("Cannot clone Cloneable type "<a name="line.532"></a>
<FONT color="green">533</FONT>                            + obj.getClass().getName(), e);<a name="line.533"></a>
<FONT color="green">534</FONT>                    } catch (final InvocationTargetException e) {<a name="line.534"></a>
<FONT color="green">535</FONT>                        throw new CloneFailedException("Exception cloning Cloneable type "<a name="line.535"></a>
<FONT color="green">536</FONT>                            + obj.getClass().getName(), e.getCause());<a name="line.536"></a>
<FONT color="green">537</FONT>                    }<a name="line.537"></a>
<FONT color="green">538</FONT>                }<a name="line.538"></a>
<FONT color="green">539</FONT>                @SuppressWarnings("unchecked")<a name="line.539"></a>
<FONT color="green">540</FONT>                final T checked = (T) result;<a name="line.540"></a>
<FONT color="green">541</FONT>                return checked;<a name="line.541"></a>
<FONT color="green">542</FONT>            }<a name="line.542"></a>
<FONT color="green">543</FONT>    <a name="line.543"></a>
<FONT color="green">544</FONT>            return null;<a name="line.544"></a>
<FONT color="green">545</FONT>        }<a name="line.545"></a>
<FONT color="green">546</FONT>    <a name="line.546"></a>
<FONT color="green">547</FONT>        /**<a name="line.547"></a>
<FONT color="green">548</FONT>         * &lt;p&gt;Clone an object if possible.&lt;/p&gt;<a name="line.548"></a>
<FONT color="green">549</FONT>         *<a name="line.549"></a>
<FONT color="green">550</FONT>         * &lt;p&gt;This method is similar to {@link #clone(Object)}, but will return the provided<a name="line.550"></a>
<FONT color="green">551</FONT>         * instance as the return value instead of {@code null} if the instance<a name="line.551"></a>
<FONT color="green">552</FONT>         * is not cloneable. This is more convenient if the caller uses different<a name="line.552"></a>
<FONT color="green">553</FONT>         * implementations (e.g. of a service) and some of the implementations do not allow concurrent<a name="line.553"></a>
<FONT color="green">554</FONT>         * processing or have state. In such cases the implementation can simply provide a proper<a name="line.554"></a>
<FONT color="green">555</FONT>         * clone implementation and the caller's code does not have to change.&lt;/p&gt;<a name="line.555"></a>
<FONT color="green">556</FONT>         *<a name="line.556"></a>
<FONT color="green">557</FONT>         * @param &lt;T&gt; the type of the object<a name="line.557"></a>
<FONT color="green">558</FONT>         * @param obj  the object to clone, null returns null<a name="line.558"></a>
<FONT color="green">559</FONT>         * @return the clone if the object implements {@link Cloneable} otherwise the object itself<a name="line.559"></a>
<FONT color="green">560</FONT>         * @throws CloneFailedException if the object is cloneable and the clone operation fails<a name="line.560"></a>
<FONT color="green">561</FONT>         * @since 3.0<a name="line.561"></a>
<FONT color="green">562</FONT>         */<a name="line.562"></a>
<FONT color="green">563</FONT>        public static &lt;T&gt; T cloneIfPossible(final T obj) {<a name="line.563"></a>
<FONT color="green">564</FONT>            final T clone = clone(obj);<a name="line.564"></a>
<FONT color="green">565</FONT>            return clone == null ? obj : clone;<a name="line.565"></a>
<FONT color="green">566</FONT>        }<a name="line.566"></a>
<FONT color="green">567</FONT>    <a name="line.567"></a>
<FONT color="green">568</FONT>        // Null<a name="line.568"></a>
<FONT color="green">569</FONT>        //-----------------------------------------------------------------------<a name="line.569"></a>
<FONT color="green">570</FONT>        /**<a name="line.570"></a>
<FONT color="green">571</FONT>         * &lt;p&gt;Class used as a null placeholder where {@code null}<a name="line.571"></a>
<FONT color="green">572</FONT>         * has another meaning.&lt;/p&gt;<a name="line.572"></a>
<FONT color="green">573</FONT>         *<a name="line.573"></a>
<FONT color="green">574</FONT>         * &lt;p&gt;For example, in a {@code HashMap} the<a name="line.574"></a>
<FONT color="green">575</FONT>         * {@link java.util.HashMap#get(java.lang.Object)} method returns<a name="line.575"></a>
<FONT color="green">576</FONT>         * {@code null} if the {@code Map} contains {@code null} or if there is<a name="line.576"></a>
<FONT color="green">577</FONT>         * no matching key. The {@code Null} placeholder can be used to distinguish<a name="line.577"></a>
<FONT color="green">578</FONT>         * between these two cases.&lt;/p&gt;<a name="line.578"></a>
<FONT color="green">579</FONT>         *<a name="line.579"></a>
<FONT color="green">580</FONT>         * &lt;p&gt;Another example is {@code Hashtable}, where {@code null}<a name="line.580"></a>
<FONT color="green">581</FONT>         * cannot be stored.&lt;/p&gt;<a name="line.581"></a>
<FONT color="green">582</FONT>         */<a name="line.582"></a>
<FONT color="green">583</FONT>        public static class Null implements Serializable {<a name="line.583"></a>
<FONT color="green">584</FONT>            /**<a name="line.584"></a>
<FONT color="green">585</FONT>             * Required for serialization support. Declare serialization compatibility with Commons Lang 1.0<a name="line.585"></a>
<FONT color="green">586</FONT>             *<a name="line.586"></a>
<FONT color="green">587</FONT>             * @see java.io.Serializable<a name="line.587"></a>
<FONT color="green">588</FONT>             */<a name="line.588"></a>
<FONT color="green">589</FONT>            private static final long serialVersionUID = 7092611880189329093L;<a name="line.589"></a>
<FONT color="green">590</FONT>    <a name="line.590"></a>
<FONT color="green">591</FONT>            /**<a name="line.591"></a>
<FONT color="green">592</FONT>             * Restricted constructor - singleton.<a name="line.592"></a>
<FONT color="green">593</FONT>             */<a name="line.593"></a>
<FONT color="green">594</FONT>            Null() {<a name="line.594"></a>
<FONT color="green">595</FONT>                super();<a name="line.595"></a>
<FONT color="green">596</FONT>            }<a name="line.596"></a>
<FONT color="green">597</FONT>    <a name="line.597"></a>
<FONT color="green">598</FONT>            /**<a name="line.598"></a>
<FONT color="green">599</FONT>             * &lt;p&gt;Ensure singleton.&lt;/p&gt;<a name="line.599"></a>
<FONT color="green">600</FONT>             *<a name="line.600"></a>
<FONT color="green">601</FONT>             * @return the singleton value<a name="line.601"></a>
<FONT color="green">602</FONT>             */<a name="line.602"></a>
<FONT color="green">603</FONT>            private Object readResolve() {<a name="line.603"></a>
<FONT color="green">604</FONT>                return ObjectUtils.NULL;<a name="line.604"></a>
<FONT color="green">605</FONT>            }<a name="line.605"></a>
<FONT color="green">606</FONT>        }<a name="line.606"></a>
<FONT color="green">607</FONT>    <a name="line.607"></a>
<FONT color="green">608</FONT>    }<a name="line.608"></a>




























































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